Round balers of the open throat design generally include a variably sized, bale forming chamber provided between spaced baler side panels, and defined by a series of side-by-side belts rotatably supported between the side panels. Also included is an upper roller arrangement and a lower roller arrangement which cooperate with one or more runs of the belts to form a bale starting chamber into which crop material is unobstructedly fed by the roller arrangements and a pick-up assembly.
While balers of such construction are preferred because of the wide-open nature of their feeding throats, some designs continue to include independent packing or compressing mechanisms in the vicinity of the bale forming chamber to maintain the tightness of the bale being formed. In addition, open throat round balers are also provided with various tensioning arrangements for ensuring the tautness of the belts throughout the bale formation. Many of these tensioning arrangements continue to be overly complicated using different arrangements of rollers or shafts, arms, springs and the like.
Accordingly, it is an object of the present invention to provide an improved belt-type, round baler which offers the advantages of an open throat configuration without necessity for separate packing or compressing mechanisms. It is a further object of the invention to provide a simplified belt tensioning device which is readily incorporated into the upper roller arrangement forming the bale starting chamber and is automatically actuable to tension the belts as the bale is progressively formed.
In one aspect of the invention, a round baler for forming round bales of crop material includes a plurality of side-by-side belts trained for movement between a starting position and a finish position around a plurality of stationary rollers including a forward baler roller and a rear baler roller spaced apart from the forward baler roller. Upper and lower roller arrangements are continuously engageable with the crop material. A bale starting chamber is defined by the upper roller arrangement, the lower roller arrangement and a run of the belts extending between the forward baler roller and the rear baler roller. A belt tracking and tensioning device is interposed between the forward baler roller and the rear baler roller. The belt tracking and tensioning device functions to vary the tension on the belts during movement of the belts between the starting position and the finished position in response to growth of the bale. The belt tracking and tensioning device is preferably mounted to the upper roller arrangement.
In the preferred embodiment, the upper roller arrangement consists of a stripping roller and an initial bale forming roller located parallel to, beneath and forwardly of the stripping roller. The belt tracking and tensioning device includes bracket structure pivotally mounted to the stripping roller. The bracket structure defines a pair of spaced ends, a first one of which is pivotally mounted to the stripping roller. The belt tracking and tensioning device further includes at least one guide roller mounted to a second end of the bracket structure. The at least one guide roller is located above and is supported against the belts on the stripping roller by the bracket structure. The belt tracking and tensioning device is located outside the bale starting chamber and is movable in a forward direction in response to bale growth. The belt tracking and tensioning device preferably includes a first guide roller engageable with the belts, and a second guide roller engageable with the belts and spaced from the first guide roller by the bracket structure. The first guide roller and the second guide roller are both located above the upper roller arrangement, and the belts are located between the upper roller arrangement and the first and second guide rollers. The first guide roller functions to maintain the belts in a predetermined relationship relative to the upper roller arrangement during bale growth. The forward pivoting movement of the bracket structure and the first and second guide rollers, caused by engagement of the belts with the first guide roller during bale growth, functions to exert increasing tension on the belts to increase the compressive force exerted on the crop material by the belt, as the bale increases in diameter. The lower roller arrangement is in the form of a single floor roller mounted rearwardly of the upper roller arrangement.
Another aspect of the invention relates to a round baler for forming round bales of crop material having a plurality of side-by-side belts trained about a series of stationary baler rollers for movement between a starting and a finish position. The baler includes an upper roller arrangement and a lower roller arrangement, both of which are engageable with the crop material and cooperable with a run of the belts to define a bale starting chamber. The improvement of the invention resides in a mechanism for maintaining the belts in a predetermined relationship relative to the upper roller arrangement during all phases of bale growth and, preferably, for tensioning the belts between the starting position and finish position. The mechanism includes a bracket pivotably mounted to one of the roller arrangements and at least one guide roller mounted on the bracket and engageable with the belts. The at least one guide roller is shiftable along an arcuate path during bale formation due to pivoting movement of the bracket in response to bale growth to maintain the spacing of the belts relative to the upper roller arrangement while maintaining the operative relationship of the upper roller arrangement relative to the bale forming chamber as the bale grows therein. The mechanism preferably also includes a second guide roller mounted on the bracket in spaced relationship to the first-mentioned guide roller and the second guide roller is also engageable with the belts to increase tension on the belts as the bale grows. The diameters of the first-mentioned and second guide rollers are less than the diameter of the rolls in the roller arrangements.
Yet another aspect of the invention relates to a round baler for forming round bales of crop material and having a plurality of side-by-side belts trained about a series of baler rollers for movement between a starting position and a finish position. The baler includes a driven stripping roller and a driven floor roller, both of which are engageable with the crop material and cooperable with a run of the belts to define a bale starting chamber. The improvement of the invention resides in a mechanism for tensioning the belts between the starting position and finish position, and comprises a bracket pivotably mounted to the stripping roller. A first guide roller is mounted to the bracket and is engageable with the belts, and a second guide roller is mounted to the bracket in spaced relationship from the first guide roller and is also engageable with the belts. The bracket is pivoted relative to the stripping roller during bale formation by engagement of the bale with the first guide roller through the belts, which results in movement of the first and second guide rollers to increase tension on the belts as the bale grows. The bracket preferably has a first leg and a second leg diverging from a common intersection thereon. In a preferred form, the first guide roller is mounted for rotation at the common intersection, the second guide roller is mounted for rotation on the first leg, and the second leg is pivotably mounted to the stripping roller.
Various other objects, features and advantages of the invention will be made apparent from the following description taken together with the drawings.